Method of making multi element self-gripping device having cooperating gripping elements

ABSTRACT

A self-gripping device is disclosed and includes a plurality of upright gripping elements stiffly attached to a base. The gripping elements are adapted to cooperate in groups of at least two for self-gripping engagement with a receiving material. Such gripping elements can include a stem and an upper portion having a plurality of arms which are adapted to cooperate with each other for self-gripping engagement.

United States Patent I1 1 Brumlik A r. 29 1975 METHOD OF MAKING MULTIELEMENT 3.123.080 3/1964 Brcnn-Albertoni 24/204 ux SELF-GRIPPING DEVICEHAVING i COOPERATING GRIPPING ELEMENTS 51371345 6/1968 2 1/204 [76]Inventor: George C. Brumlik, 154 Upper 3550.223 l2/l970 Erb 24/204 %lMmtclm FOREIGN PATENTS OR APPLICATIONS 2047,24 12/l97l France 24/204[22] Filed: Sept. 26, 1973 [21] Appl. No: 401,085 PrimaryExaminer-Charlie T. Moon Attorney, Agent, or FirmBurgess, Dinklage &Related US. Application Data Sprung [63] Continuation of Scr. No.298,906. Oct. 19, 1972.

flbimdoncfl- 57 ABSTRACT [52] U 5 Cl 29/412, 74/704. 28/72 Aself-gripping device is disclosed and includes a plu- 4 2 5 1 139/46rality of upright gripping elements stiffly attached to a 51 Int. Cl. H:B23ip 17/00 base" The gripping elements are adapted [58] Field of Search29/412. 415, 445, 432. groups of at least two for selfgfippingengagement 79/41] 437 7 418 24/7O4 28/72 with a receiving material. Suchgripping elements can 5 i 5 139/; include a Stem and an upper portionhaving a plurality of arms which are adapted to cooperate with each [56]References Cited other for self-gripping engagement.

UNITED STATES PATENTS 3 Claims, 17 Drawing Figures 1717.437 9/1955Mcstral 24/204 UX METHOD OF MAKING MULTIELEMENT SELF-GRIPPING DEVICEHAVING COOPERATING GRIPPING ELEMENTS This is a continuation, ofapplication Ser. No. 298,906. filed Oct. 19. 1972. now abandoned.

BACKGROUND This invention relates to self-gripping devices having aplurality of gripping elements which are adapted to cooperate in groupsof at least two for self-gripping engagement with a receiving material.

Self-gripping devices have been known for some time but only recentlyhave they begun to replace conventional fastening devices such asstaples. nails. adhesives and the like. In general, self-grippingdevices perform many unique functions which conventional fastenerscannot provide. For instance. there is unlimited freedom ofself-gripping engagement over an area by virtue of the vast number ofgripping sites in a receiving material. This has the effect ofeliminating alignmenet criticalities that seriously hamper conventionalfasteners. involving mating specific fastening sites such as a bore orhole with corresponding fastening devices such as a screw or bolt.

A self-gripping connection can be formed simply by hand without the needfor special tools. Once the selfgripping connection is formed it can bepulled apart due to the reversible nature of the self-grippingconnections. This provides for invisible attachment that leaves no marksonce the connection is pulled apart and established elsewhere on thesurface. This is especially true for carpet covered walls and ceilingswhich are finding increased used as an interior surface finish.

Also, a plurality of gripping elements in a selfgripping devicecooperate to provide the required amount of self-gripping holding forceand distribute same over a predetermined area thus avoiding localizedstress concentrations such as occurs with conventional fasteners.

Another desirable feature is that the gripping elements of a device areinherently flexible which allows a self-gripping connection toaccommodate dimensional changes caused by large thermal coefficients ofexpansion that occur between similar or dissimilar articles connected toeach other by a self-gripping mechanism. This prevents buckling andcracking ofjoined articles.

One more capability of self-gripping devices is the ability to form aself-gripping connection between articles on any face. edge or corner bysimply bringing any pair of these into contact at the desired location.

With the everincreasing use and sophistication of self-gripping devices.the ability of self-gripping devices to form unique self-grippingconnections for particular applications becomes important.

SUMMARY The self-gripping device of the invention comprises a pluralityof upright gripping elements stiffly attached to a base. said grippingelement being adapted to cooperate in groups of at least two with atleast one member of the group having self-gripping means oriented in thedirection of the other member of the group for selfgripping engagementwith a receiving material. In a preferred embodiment the grippingelements comprise a stem and an upper portion having a plurality of armseach having self-gripping means adapted to cooperate with each other forself-gripping engagement with a receiving layer.

DESCRIPTION OF THE DRAWINGS FIGS. 1a through 1e are side elevationalviews of gripping elements suitable for use in the device of theinvention.

FIG. 2 is a side elevational view partially in section and partiallybroken away illustrating a group of gripping elements suitable for usein the device of the invention.

FIG. 3 is a cross-sectional view illustrating several embodiments of theinvention.

FIG. 4 is a perspective view illustrating an integral structure fromwhich the self-gripping device of the invention can be formed.

FIG. 5 is a cross-sectional view partly broken away taken along line 5-5of FIG. 4.

FIG. 6 is a top plan view partly broken away illustrating several waysin which the device of the invention can be formed from the structureshown in FIG. 4.

FIGS. 7a and 7b are side elevational views partly broken awayillustrating several embodiments of the device of the invention.

FIG. 8 is a perspective view of apparatus suitable for forming thestructure of FIG. 4.

FIG. 9 is an end elevational view illustrating a further embodiment ofthe self-gripping device of the invention.

FIG. 10 is a side elevational view of an alternate embodiment ofcooperating gripping elements according to the invention and FIG. 11 isa side elevational view partly in crosssection illustrating an alternateembodiment for forming cooperating groups of gripping elements from acontinuous filament such as a wire.

DESCRIPTION Referring now to the drawings and in particular FIG. 2, theself-gripping device of the invention is shown to include a base 20having a plurality of upright gripping element 10 stiffly attachedthereto. The gripping elements 10 include an upright stem 12 andself-gripping means 14 which cooperate with similar means of adjacentgripping element 10 for self-gripping engagement at 40. Thus, adjacentgripping elements 10 can cooperate for self-gripping engagement formingwhat can be termed a self-gripping trap.

In FIG. 1 several embodiments are shown wherein gripping elements 10 areself-contained and include an upright stem 12 and a plurality of arms 12forming a bifurcated portion. Each of the arms 12' terminate in grippinghooks 14 which cooperate for self-gripping engagement at 40. In .FIG. 1athe gripping means 14 are shown as sharply pointed hooks and in FIG. lbthe hooks are more rounded. In FIG. 10 the arms 12' forming thebifurcated portion each have serrated edges facing each other andprovide for self-gripping engagement throughout the depth of thebifurcated portion. In FIG. It] the stem 12 is shown having threeupright arms I 12 forming a trifurcated position. The three arms 12terminate in rounded hooks which cooperate for selfgripping engagementat 40. At FIG. Ie the gripping means 14 make it possible for arms 12attached to the same stem 12 to cooperate at 40 for self-grippingengagement. It is also possible for arms 12' having gripping means 14from adjacent gripping elements 10 to cooperate at 40 for self-grippingengagement. Thus in FIG. le self-gripping cooperation at 40 can betermed an intra-element self-gripping trap and self-gripping cooperationat 40' can be termed an inter-element selfgripping trap.

Generally speaking, the upper ends of the gripping elements have apenetrating profile of shape to facilitate penetration into a receivingmaterial. This applies to the embodiments shown in FIG. I as well as tothe embodiment shown in FIG. 2. The penetrating shape may be sharplypointed as shown in FIGS. la, la and 1d, for example, or they may berounded as shown in FIGS. lb, la and 2, for example. In those instanceswhere skin irritation is to be avoided the upper end or ends of thegripping elements are rounded.

The gripping elements 10 may be formed or molded from a wide variety ofmaterials such as metal, glass, plastic or composites of these but arepreferably made of plastic or metal. Also the cross-sectional shape ofthe stem 12, the arms 12 and the gripping means 14 may be varied. Forexample, they may be rectangular, crescent shape polygonal and the like.

In general, the gripping elements are sufficiently stiff such that theyresist deflection which would otherwise prevent them from penetratingand becoming lodged in a receiving layer or material. It is alsonecessary that the gripping elements be stiffly attached to the base toenable the gripping elements to enter into self-gripping engagement.Thus the gripping elements can be attached to a base by any suitabletechnique consistent with the nature of the gripping elements and thebase. Such techniques include inserting the base of the grippingelements in or through the base with or without the use of additionaltechniques such as welding, heat sealing, or using adhesives. The lattertechniques can also be used to attach the gripping elements withoutinserting same. As discussed below the gripping elements 10 can also beintegrally formed with the base 20.

Referring now to FIG. 3, a self-gripping device of the inventioncomprising sheet and upright gripping elements as shown in FIG. 1a isshown in self-gripping engagement with a receiving layer 42 which isfibrous in nature for purposes of illustration.

For certain applications, it is desirable to utilize a receiving layersuch as that shown in FIG. 3 as a protective layer for the grippingelements 10 which can be stripped off to prepare the device forself-gripping engagement. The use of a protective layer makes itpossible to ship and handle the device without irritation to the user orpremature gripping engagement. A protective layer has a thickness equalto or greater than the height of the gripping elements 10 and can bereadily utilzed with any various embodiments of the invention such asthose shown in FIGS. 1, 2, 7 and 9, for example.

It is also possible to use the receiving layer 42 as a component part ofthe device of the invention. In this instance the layer 42 is made of aresilient material such as felt, carpet-like materials, sponge, plasticand can be foam and the like, that remains in place over the grippingelements 10 forming what can be called a hybrid self-gripping surface.The gripping elements 10 in FIG. 3 can extend below, to or beyond thesurface of layer 42. Thus when layer 42 is compressed, the elements 10are exposed and protrude out of the layer 42 and are then capable ofself-gripping engagement with a receiving layer of material or a similarhybrid selfgripping device.

Referring now to FIG. 4, the self-gripping device of the invention ispreferably formed from an integral structure having base 20 and aplurality of substantially parallel ribs 22 which have a cross-sectionalshape or profile which defines gripping elements sutable for cooperativeself-gripping engagement according to the invention. The ribs 22 in FIG.4 have a profile corresponding to the gripping element of FIG. la forpurposes of illustration. It is also possible to position ribs 22 toproduce a structure wherein adjacent elements cooperate forself-gripping engagement such as shown in FIG. 2.

The ribs 22 are cut into spaced apart gripping elements 10 by removingportions of the rib as shown in FIG. 5 wherein the rib can be cut at aangle relative to the base and portions 24 removed to form perpendiculargripping elements or it can be cut at an angle and portions 26 removedto form angled gripping elements 10 also as shown in FIG. 5. Inaddition, angled or pointed elements 10 can be formed by cutting andremoving wedged shape portions 27 from the ribs 22.

It is also possible to remove segments of the base underlying theportions of the rib to be removed between adjacent gripping elements.For example, in FIG. 6 reference numeral 28 is used to designate squareand round perforations through ribs 22 and base 20 which forms spacedapart gripping elements 10 integral with the performated base 20. Theperforations 28 can be in a random or uniform pattern and can be thesame or different as illustrated in FIG. 6. In addition, the base 20 canbe cut or slit along dotted lines 21 to form strip or patch likeself-gripping devices in contrast to the sheet like structure shown inFIG. 4.

As shown in FIG. 7a and 7b the ribs 22 can be inclined at an angle toform inclined gripping elements 10 and gripping elements can be formedon both sides of the base 20. Also shown in FIG. 7b is the use ofconventional gripping elements in combination with the trap typeelements of the invention.

Suitable apparatus for forming the integral structure shown in FIG. 4 isillustrated in FIG. 8 and includes an extruder 50 provided with anelongated slot type die 52 having an opening 54 which corresponds to thecrosssectional profile of the integral structure to be extruded.Extrudable material is melted and conveyed in the extruder 50 and forcedout of the die in a hot plastic state. The ribs 22 may be formedstraight as shown or can be formed in a way or zig zag pattern usingtwopart moving dies as are known in the art. It is also possible toextrude a composite structure using coaxial dies or composite extrudingdevices as are known in the art. Such a composite structure couldinclude, for example, a first material for the base 20, a secondmaterial for the stem 12 and a third material for the gripping means 14.Also shown in FIG. 8 is a rotating cutting wheel 56 which is capable ofmoving vertically and transversely with respect to ribs 22 to removeportions thereof to form integral gripping elements 10.

Related integral structures. grips, elements formed therefrom andmethods and apparatus for forming same are disclosed in my co-pendingapplication Ser. No. 214,871, filed Jan. 3, 1972.

In FIG. 9 a circular structure is illustrated which can be readilyextruded and simultaneously or sequentially slit and laid flat to form asheet or strip like selfgripping device according to the invention.

Integral structures such as shown in FIG. 4 can be formed from materialsincluding metals and plastics. Suitable metals include aluminum andaluminum alloys, copper, copper alloys, iron and the like. Suitableplastics include extrudable thermosetting pheonolic compositions and thelike and extrudable thermoplastics such as polyethylene, polypropylene,polystyrenes. polycarbonates, polysulfones, nylons and the like.

The term cut includes techniques such as slicing. slitting, stamping,punching and the like. It is also possible to chemically or electricallycut an extruded structure to form the spaced apart gripping elementsusing etching electric arc techniques and the like.

The self-gripping devices are adapted to penetrate and become loged in areceiving material or layer which can be formed from a variety ofmaterials including woven, non-woven, and knitted fabrics and fibers,carpets and carpet'like materials, foam rubber and plastics, wood, cork,sponge, leather, paper, cardboard, corrugated carboard, metal andplastic mesh, expanded and perforated sheet materials and composites andlaminates including any of the foregoing. The gripping trap of theinvention is especially suited for gripping fibrous materials.

Especially suitable receiving materials and structures are disclosed inmy copending applications Ser. Nos. 126,708, and 126,706, both filedMar. 22, I97] and now abandoned, and Ser. No. 154,589, filed June 18,1971, now abandoned.

The nature of the self-gripping action by the gripping elements may bepermanent or reversible depending upon the nature of the grippingelements and the receiving material that comes into self-grippingengagement with the gripping elements. For example, the grippingelements may be rigid to provide more permanent or tenaciousself-gripping action or they may be resilient to facilitate removal froma receiving layer. The degree of self-gripping also depends in part uponthe shape of the gripping elements.

In its simplest form the self-gripping device of the invention caninclude a base 20 having upright cooperating elements 11 and 12 stifflyattached thereto. The member 12 is provided with a self-gripping detentor protrusion 14 which cooperates with the generally linear element 11for self-gripping engagement at 40. Stated differently, theself-gripping means 14 is oriented in the direction of the other memberor element 11 thus making it possible to cooperatively self-grip at 40as shown. The cooperating elements of FIG. can be formed from a commonstem as in FIG. 1 or they can be individually attached to a base asshown in FIG. 10. The gripping means 14 shown in FIG. 10 can have any ofthe configurations shown in FIGS. 1 and 2 including combinationsthereto.

FIG. 11 illustrates an embodiment wherein a filament such as metal wireis stretched or otherwise inserted in or through the base to formheart-shaped configurations which are cut as indicated by the dottedlines to form a gripping trap according to the invention whereinadjacent members 12' cooperate for self-gripping engagement at 40. Themembers 12 can be formed in pairs by bending a linear element into theheart-shaped configuration shown and inserting the lower ends thereofinto the base 20 or otherwise attaching same thereto. It is alsopossible to utilize other configurations which when cut will formcooperating gripping elements 12'. For example, a linear element such asa wire can be looped once or more times in place of the upper portion ofthe heart-shaped configuration and cut horizontally or vertically toform the cooperating gripping elements. The loop 66 when cuthorizontally, or vertically provides cooperating elements whichphysically overlap lending a spring action to the cooperatingselfgripping capability.

Thus, the self-gripping device of the invention incorporating theembodiment of FIG. 11 have groups of gripping elements 12' with grippingmeans 14 which cooperate for self-gripping engagement at 40. Thegripping elements 12' have their origin in loops stiffly attached to thebase 20 having a depression 64 or a curl 66 oriented interiorly of theloop as shown. In other words the depression 64 and the curl 66 extenddownward from the upper lobe portion 62 of the respective loops towardsthe base 20. The loops are severed or separated horizontally orvertically at the depression 64 or the curl 66 forming the grippingelements 12. In a preferred embodiment a plurality or series of theloops have their origin in a common linear member 60 which as previouslydescribed can be stitched into or through the base.

The cooperating groups of gripping elements shown in FIG. 11 can be madeaccording to the invention by stiffly mounting a plurality of loops to abase in the generally upright position. Each of the loops is formedbefore or after mounting on the base with a depression 64 or curl 66oriented as described above. The depressions or curls are cut verticallyor horizontally as indicated by the dotted lines in FIG. 11 therebyforming groups of cooperating gripping elements 12' having grippingmeans 14 oriented towards each other for cooperative self-grippingengagement at 40.

The cooperating self-gripping device shown in FIG. 11 can be made frommonofilament or yarn made of metal or plastic wire and installedcontinuously or individually as described above. A linear element can beembedded in the base or stretched through using conventional sewingtechniques. The further linear element 30 can be inserted on theopposite side of the base through loops protruding therefrom as shown toprevent the cooperating gripping elements from being pulled from thebase. The cooperating gripping elements shown in FIG. 11 can be fusedinto or onto the base and can be surface mounted using adhesive,welding, and like techniques. In this embodiment, the base 20 can be afabric which can be rigid or flexible or made rigid after installing thelinear looped arrangement as shown in FIG. 11. The base 20 can also bemade of a plastic or elastomeric sheet material or it can form the outersurface or skin of an article.

The gripping elements of the self-gripping devices of the invention willgenerally range in height from about 0.001 to about 0.75 inch.

The self-gripping device of the invention may be used in a variety ofways to efficiently and quickly render virtually any surface or articleself-gripping. The device of the invention can be readily used byindividuals or commercial users to render selected areas of articles orentire articles self-gripping such as carpets, fabrics, felts, wallcladded materials, panels, tiles, sheets, filters, decorative trim andthe like.

What is claimed is:

1. Method for making a self gripping device which comprises stiffiymounting a plurality of loops to a base in generally upright position,said loops having a curl have their origin in a common linear member.

3. Process of claim 2 wherein said linear member is stitched into orthrough said base.

1. Method for making a self gripping device which comprises stifflymounting a plurality of loops to a base in generally upright position,said loops having a curl interiorly oriented with respect to said loop,horizontally severing said curls relative to said base thereby formingpairs of overlapping, cooperating gripping elements.
 2. Process of claim1 wherein a plurality of said loops have their origin in a common linearmember.
 3. Process of claim 2 wherein said linear member is stitchedinto or through said base.